Answer to question 1 -- burning wood and forrest by products release mercury. This is speculated to be from generations of coal burning which releases mercury into the air, and rains down on trees which absorb it.

In present day, aluminum levels are skyrocketing for some reason, and this is killing trees and wildlife.

Many trees are seeding early because they think they are dying and it is thought that aluminum is the cause.

??I recall a documentary from Brazil converting trash into energy, I wonder how can we know what harvesting method is the most profitable for a certain location ?

I think every situation is similar but different. If there is enough steady flow of trash, it could be a usable source of energy if done cleanly and responsibly.

Brazil has a bounty of sugar cane used to produce ethanol and is mostly energy independant in a renewable way. Unfortunatly, we all can't grow sugar cane. If we did, the world would be a sweeter place. (and no high fructose corn syrup)!!!

???? Thank you for the nice lecture series. One source of energy, which we should harness is human energy. What do you think of human powered devices to genrate power/charge batteries etc? Do we have devices/machine, which can be used easily to generate energy? Thx.

I always thought that if we could harness the energy that kids have, we could light all our cities.

It's a slippery slope though to use human energy as a source of power. Maybe in a gym, the machines can offer resistance by generating electricity for the facility.

?? Thank you for the nice lecture series. One source of energy, which we should harness is human energy. What do you think of human powered devices to genrate power/charge batteries etc? Do we have devices/machine, which can be used easily to generate energy? Thx.

Answer to question 4 -- the valueable by product of cold fusion is helium 3, an isotope of helium that the nuclear industry wants to use in its next generation of reactors. It is very scarce here on earth.

??What do you think of the backyard biodiesel cookers? Would you encourage this level of do-it-yourself energy independance?

They work but can be dirty, smelly, and take time to do the titration process, the wash process, and the extraction process. They also require a good source of anahydrouse methane which should be stored in a concrete block building. But, if you have the source of vegetable oil, it works, and the process can be automated somewhat.

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